By ALIYAH BARUCHIN

Among Americans with asthma, minority children are in by far the worst situation. The numbers are striking: in the United States, 20 percent of Puerto Rican children, or one in five, have asthma. Among African-American youngsters, the rate is 13 percent, compared with the national childhood average of 8 percent. In addition, since 1999 asthma-related mortality rates have dropped for Americans as a whole, but not for minority children.

By the Numbers

According to the National Center for Health Statistics, African-American and Puerto Rican children are six times as likely as white children to die of asthma. In minority children, “the prevalence of asthma is about 40 percent higher, but the difference in the adverse outcomes is three times, four times higher for hospitalizations,” said Dr. Lara Akinbami, a researcher at the center who tracks childhood asthma. “Given that we have the tools to prevent those things, that does reach the level of a public health crisis.”

Several factors contribute to the disparity. Socioeconomic status is certainly central, particularly in terms of environment. Children in poor inner-city communities are disproportionately exposed to both indoor and outdoor allergens — cockroaches, mice, mold, dust, cigarette smoke, automobile exhaust, soot — that can trigger breathing problems.

“If you look at inner-city children, they’re sensitized to more allergens and exposed to more allergens at higher levels in their homes, allergens that it’s difficult for them to avoid,” said Dr. Andrew Liu of the National Jewish Medical and Research Center in Denver. Dr. Liu is part of the Inner-City Asthma Consortium, a federally sponsored research initiative at 10 medical centers nationwide that looks at the severity of asthma in cities and is testing treatments to block the allergic response.

Chronic lack of access to outpatient health care and the poorer quality of care in inner-city neighborhoods is another crucial factor. Successful asthma care depends on regular medical maintenance, and poor urban children have less reliable access to doctors’ offices and clinics, more often relying on emergency room visits for treatment.

More generally, keeping up with treatment can be daunting for anyone. “Asthma is a very high-maintenance disease,” Dr. Akinbami said. “You can really control it and live without symptoms, but it’s a lot of work. And if you have a lot of other challenges, it’s much harder to really get organized and motivated to do the things that are necessary.”

Patterns of medication use may differ as well. Inner-city children with asthma tend to overuse fast-acting rescue medications like albuterol at the expense of long-acting steroids like Flovent or Pulmicort, mainstays of asthma control. Language and other social barriers often prevent doctors from accurately assessing how asthma patients are using their medicines at home.

Genetic factors may also play a role. African-Americans are more likely to have a genetic characteristic that makes them more vulnerable to the adverse effects of overusing rescue medications. And even after controlling for socioeconomic factors, African-American children tend to have higher levels of allergies, which are related to asthma in about 85 percent of cases, than white children. Among Puerto Rican children, the incidence of asthma is equally high both in mainland cities and on the island of Puerto Rico, pointing to a possible genetic predisposition to developing the disease.

But at the moment, genetics is secondary to the pressing need for quality care. Several city-based or regional asthma intervention programs have had significant success in raising awareness among parents and doctors, reducing exposure to allergens in homes and schools, and improving care for children.

From 1997 to 2001 during New York City’s Childhood Asthma Initiative — which ran the memorable “I have asthma, but asthma doesn’t have me” advertising campaign — the rate of childhood hospitalizations for asthma in the city decreased by more than a third. The rates of emergency room visits and hospital stays have decreased sharply in central Connecticut, which has the Easy Breathing program to teach practitioners how to more accurately identify asthma in children and meet National Institutes of Health guidelines for care.

At the end of the day, what makes the statistics about minority children and asthma remarkable is that there is actually no mystery to asthma management. Successful intervention programs are straightforward, fact-based and, in theory, easily replicated.

“Even though we don’t know how to prevent asthma, we really do know how to control the symptoms,” Dr. Akinbami said. “These programs can make a difference, and change the outcomes for these children.”